Electrical wiring devices, such as switches, receptacles, and sensor devices, are often provided in duplex or triplex configurations. For example, a duplex receptacle includes two sets of female contacts in each set. If the receptacle is a grounded receptacle, an electrical contact is provided for a ground terminal as well as line and neutral contacts. A duplex switch also includes two sets of switch contacts. A triplex device, obviously, includes three sets of contacts. Electrical wiring devices include wiring terminals for electrically coupling each electrical contact to a wire in the electrical circuit. In an ungrounded receptacle, the ground contact and corresponding ground terminal are eliminated.
Duplex or triplex electrical wiring devices such as switches and receptacles may have both a single and a split (or dual) circuit operating capability for operation in a single or a split (or dual) circuit configuration. In the following discussion duplex devices are discussed for ease of illustration. Those of ordinary skill in the art will understand that the discussion is applicable to triplex devices as well. In the split circuit mode each set of terminals (switch or receptacleterminals) receives electrical power from an independent circuit. On the other hand, in the single circuit mode, one circuit supplies power to both sets of terminals. The circuit that is coupled to a first set of terminals is fed through to the other set of terminals. Further, the same circuit may also provide power to additional downstream wiring devices. What is needed are wiring devices that may be configurable in the field as either single circuit or split circuit devices.
In one approach that has been considered, a slotted tab is disposed within an electrical wiring device that connects the first set of terminals with the second set of terminals. The wiring device may be converted from a single circuit device into a split circuit device by inserting a screwdriver blade into the wiring device to break off the tab. A pair of pliers may be used to perform this operation as well. Once the wiring device is configured as a split circuit device, each set of terminals are operated independently of each other. One drawback to this approach relates to the fact that once the device is in split circuit mode it cannot be reconfigured as a single circuit device. In other words, once the tab is broken, it cannot be re-installed. Thus, the device is scrapped or used elsewhere.
There are modular wiring devices that include a single frame and individual wiring devices such as receptacles or switches configurable to the frame. Each individual wiring device has a set of terminals. The sets of terminals are not disposed in the modular device to permit connection by a tab. Thus modular wiring devices are pre-assembled for a split circuit or single circuit configuration without ability to convert the device while in the field to the other circuit configuration.
What is needed is a wiring device that can be easily reconfigured as a single circuit device after it has been configured as a split circuit device, or vice-versa.